REACTION-TIME DISTRIBUTIONS ACROSS NORMAL FORGETTING - SEARCHING FOR MARKERS OF MEMORY CONSOLIDATION

Volunteers studied pictures of objects and were then tested for yes/no recognition at 10 min and 1 week after learning (experiment 1), or at 10 min and 4 months after learning (experiment 2). Because the gradua l consolidation of long-term memory is thought to occur across this ti me scale (weeks and months), the reaction time distributions of succes sfully retrieved items were analyzed in an attempt to detect markers o f consolidation. At each retention interval, reaction times for items retrieved successfully were well fit by a model that assumed a single underlying distribution. No evidence for a bimodal distribution of rea ction times was observed. Furthermore, there was no evidence that some small subset of items was actually retrieved faster after a long rete ntion interval than after a short interval. The results are consistent with the idea that consolidation works not to increase memory trace s trength but to change the nature of memory storage. This process occur s during the course of normal forgetting and may not be observable in the behavior of normal memory.